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HOMESERVICE MANUALSHONDA2002CIVIC SIREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 137 (ELECTRONIC THROTTLE CONTROL SYSTEM)DTC TROUBLESHOOTINGDTC P1659: ELECTRONIC THROTTLE CONTROL SYSTEM (ETCS) CONTROL RELAY OFF MALFUNCTION
2002 Honda Civic Si

DTC P1659: Electronic Throttle Control System (ETCS) Control Relay OFF Malfunction

2002 Honda Civic SiSECTION DTC P1659: Electronic Throttle Control System (ETCS) Control Relay OFF Malfunction
WARNING: This page is about a different car, the 2006 Honda Odyssey and 2005 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn the ignition switch ON (II).
  2. Clear the DTC with the HDS.
  3. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P1659 indicated? 

    1. YES  - Go to step  4.
    2. NO  - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM.
  4. Turn the ignition switch OFF.
  5. Check the No. 3 DBW (15 A) fuse in the passenger's under-dash fuse/relay box.

    Is the fuse OK? 

    1. YES  - Go to step  6.
    2. NO  - Go to step  20.
  6. Remove the electronic throttle control system (ETCS) control relay (A) from the passenger's under-dash fuse/relay box.
    Fig 1: Removing ETCS Control Relay
    G03704406Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Test the electronic throttle control system (ETCS) control relay (see POWER RELAY TEST ).

    Is the electronic throttle control system (ETCS) control relay OK? 

    1. YES  - Go to step  8.
    2. NO  - Replace the electronic throttle control system (ETCS) control relay, then go to step  28.
  8. Turn the ignition switch ON (II).
  9. Measure voltage between electronic throttle control system (ETCS) control relay 4P connector terminal No. 3 and body ground.
    Fig 2: Measuring Voltage Between ETCS Control Relay 4P Connector Terminal No. 3 And Body Ground
    G03704407Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is the battery voltage? 

    1. YES  - Go to step  10.
    2. NO  - Repair open in the wire between PGM-FI main relay 1 (FI MAIN) and the electronic throttle control system (ETCS) control relay, then go to step  27.
  10. Measure voltage between electronic throttle control system (ETCS) control relay 4P connector terminal No. 1 and body ground.
    Fig 3: Measuring Voltage Between ETCS Control Relay 4P Connector Terminal No. 1 And Body Ground
    G03704408Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is the battery voltage? 

    1. YES  - Go to step  11.
    2. NO  - Repair open in the wire between the electronic throttle control system (ETCS) control relay and the UNDER-HOOD FUSE/RELAY BOX, then go to step  27.
  11. Turn the ignition switch OFF.
  12. Jump the SCS line with the HDS.
  13. Disconnect PCM connector C (44P).
  14. Connect electronic throttle control system (ETCS) control relay 4P connector terminal No. 2 to body ground with a jumper wire.
    Fig 4: Connecting ETCS Control Relay 4P Connector Terminal No. 2 To Body Ground With Jumper Wire
    G03704409Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Check for continuity between the PCM connector terminal C4 and body ground.
    Fig 5: Checking Continuity Between PCM Connector Terminal C4 And Body Ground
    G03704410Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Go to step  16.
    2. NO  - Repair open in the wire between the PCM (C4) and the electronic throttle control system (ETCS) control relay, then go to step  28.
  16. Disconnect the jumper wire.
  17. Disconnect PCM connector A (44P).
  18. Connect electronic throttle control system (ETCS) control relay 4P connector terminal No. 4 to body ground with a jumper wire.
    Fig 6: Connecting ETCS Control Relay 4P Connector Terminal No. 4 To Body Ground With Jumper Wire
    G03704411Courtesy of AMERICAN HONDA MOTOR CO., INC.
  19. Check for continuity between PCM connector terminal A20 and body ground.
    Fig 7: Checking Continuity Between PCM Connector Terminal A20 And Body Ground
    G03704412Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Go to step  33.
    2. NO  - Repair open in the wire between the PCM (A20) and the electronic throttle control system (ETCS) control relay, then go to step  28.
  20. Remove the blown No. 3 DBW (15 A) fuse in the passenger's under-dash fuse/relay box.
  21. Jump the SCS line with the HDS.
  22. Disconnect PCM connector C (44P).
  23. Check for continuity between PCM connector terminal C4 and body ground.
    Fig 8: Checking Continuity Between PCM Connector Terminal C4 And Body Ground
    G03704413Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Go to step  24.
    2. NO  - Replace the No. 3 DBW (15 A) fuse, then go to step  28.
  24. Remove the electronic throttle control system (ETCS) control relay (A) from the passenger's under-dash fuse/relay box.
    Fig 9: Removing ETCS Control Relay
    G03704414Courtesy of AMERICAN HONDA MOTOR CO., INC.
  25. Check for continuity between PCM connector terminal C4 and body ground.
    Fig 10: Checking Continuity Between PCM Connector Terminal C4 And Body Ground
    G03704415Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the electronic throttle control system (ETCS) control relay and the PCM (C4), then go to step  28.
    2. NO  - Go to step  26.
  26. Check for continuity between electronic throttle control system (ETCS) control relay 4P connector terminal No. 1 and body ground.
    Fig 11: Checking Continuity Between ETCS Control Relay 4P Connector Terminal No. 1 And Body Ground
    G03704416Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the No. 3 DBW (15 A) fuse and the electronic throttle control system (ETCS) control relay, then go to step  28.
    2. NO  - Replace the No. 3 DBW (15 A) fuse, then go to step  28.
  27. Turn the ignition switch OFF.
  28. Reconnect all connectors.
  29. Turn the ignition switch ON (II).
  30. Reset the PCM with the HDS.
  31. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  32. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - If DTC P1659 is indicated, check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM, then go to step  1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
    2. NO  - Troubleshooting is complete.
  33. Update the PCM if it does not have the latest software, or substitute a known-good PCM (see PCM UPDATING AND SUBSTITUTION FOR TESTING ).
  34. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - If DTC P1659 is indicated, check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM, then go to step  1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
    2. NO  - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ).
RENDER: 1.0x

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